I dunno about that, and feel like you might be underestimating the community a bit. Honestly, while I had an account pre-Discourse, I rarely commented except to provide occasional supporting links. Generally I didn’t feel like logging into BB or Disqus and would anon-like plenty of stuff.
Seems to be the case over at the AVClub too; stuff that clearly deserve it receive a strong number of likes from a mixture of both reg’d accts and anons. (I mention AVC specifically, as it seems like another place where happy mutants have congregated en masse, and–with top-notch mod-help, no doubt–managed to keep swept pretty clean of trollies.)